Spermine deficiency in Gy mice caused by deletion of the spermine synthase gene.
Two mouse mutations gyro (Gy) and hypophosphatemia (Hyp) are mouse models for X-linked hypophosphatemic rickets and have been shown to be deleted for the 5' and 3' end of the mouse homolog of PHEX (phosphate regulating gene with homologies to endopeptidases on the X chromosome; formerly called PEX), respectively. In addition to the metabolic disorder observed in Hyp mice, male Gy mice are sterile and show circling behavior and reduced viability. The human SMS (spermine synthase) gene maps approximately 39 kb upstream of PHEX and is transcribed in the same direction. To elucidate the complex phenotype of Gy mice, we characterized the genomic region upstream of Phex. By establishing the genomic structure of mouse Sms, a 160-190 kb deletion was shown in Gy mice, which includes both Phex and Sms. There are several pseudogenes of SMS / Sms in man and mouse. Northern analysis revealed three different Sms transcripts which are absent in Gy mice. Measurement of polyamine levels revealed a marked decrease in spermine in liver and pancreas of affected male Gy mice. Analysis of brain tissue revealed no gross or histological abnormalities. Gy provides a mouse model for a defect in the polyamine pathway, which is known to play a key role in cell proliferation.
Lorenz
B
B
Abteilung Medizinische Genetik, Kinderpoliklinik, Ludwig-Maximilians-Universität, Goethestr. 29, 80336 München, Germany.
Francis
F
F
Gempel
K
K
Böddrich
A
A
Josten
M
M
Schmahl
W
W
Schmidt
J
J
Lehrach
H
H
Meitinger
T
T
Strom
T M
TM
D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D002874:Chromosome Mapping; D017931:DNA Primers; D005091:Exons; D017353:Gene Deletion; D006801:Humans; D017674:Hypophosphatemia / Q000235:genetics; D007248:Infertility, Male / Q000235:genetics; D008099:Liver / Q000378:metabolism; D008297:Male; D008659:Metabolic Diseases / Q000235:genetics; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D008969:Molecular Sequence Data; D010179:Pancreas / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011544:Pseudogenes; D011700:Putrescine / Q000378:metabolism; D013095:Spermidine / Q000378:metabolism; D013096:Spermine / Q000378:metabolism*; D013097:Spermine Synthase / Q000172:deficiency / Q000235:genetics*; D013239:Stereotyped Behavior; D014960:X Chromosome
D017931:DNA Primers; D013096:Spermine; D013097:Spermine Synthase; D013095:Spermidine; D011700:Putrescine